6607310: InputContext may cause loading of swing classes even for non-Swing applets

Reviewed-by: okutsu

src/share/classes/sun/awt/im/CompositionArea.java

@@ -56,7 +56,8 @@ import javax.swing.border.LineBorder;
  * @author JavaSoft International
  */
 
-public class CompositionArea extends JPanel implements InputMethodListener {
+// This class is final due to the 6607310 fix. Refer to the CR for details.
+public final class CompositionArea extends JPanel implements InputMethodListener {
 
     private CompositionAreaHandler handler;
 

src/share/classes/sun/awt/im/InputContext.java

@@ -297,7 +297,7 @@ public class InputContext extends java.awt.im.InputContext
          */
         synchronized (source.getTreeLock()) {
             synchronized (this) {
-                if (source instanceof CompositionArea) {
+                if ("sun.awt.im.CompositionArea".equals(source.getClass().getName())) {
                     // no special handling for this one
                 } else if (getComponentWindow(source) instanceof InputMethodWindow) {
                     // no special handling for this one either